Failure of the α-factor in describing QD laser dynamical instabilities and chaos

Abstract

We show that the long-established concept of a linewidth-enhancement factor αto describe carrier-induced refractive index changes in semiconductor lasers breaks down in quantum dot (QD) lasers when describing complex dynamic scenarios, found for example under high-excitation or optical injection. By comparing laser simulations using a constant α-factor with results from a more complex non-equilibrium model that separately treats gain and refractive index dynamics, we examine the conditions under which an approximation of the amplitude-phase coupling by an α-factor becomes invalid. The investigations show that while a quasi-equilibrium approach for conventional quantum well lasers is valid over a reasonable parameter range, allowing one to introduce an α-factor as a constant parameter, the concept is in general not applicable to predict QD laser dynamics due to the different timescales of the involved scattering processes.

References in corpus (1)

• All-optical memory based on the injection locking bistability of a two-color laser diode

Cited by in corpus (7)

• Amplitude-phase coupling drives chimera states in globally coupled laser networks
• Optoelectronic device simulations based on macroscopic Maxwell-Bloch equations
• Square wave excitability in quantum dot lasers under optical injection
• Stability of Optically Injected Two-State Quantum-Dot Lasers
• Injection locking of quantum dot microlasers operating in the few photon regime
• Ramsey fringes in a room temperature quantum dot semiconductor optical amplifier
• Interpretable disorder-promoted synchronization and coherence in coupled laser networks